With the development of an image technology and a digital technology, a stereoscopic video technology that further increases animation of images and enables persons watching the images to increase the feel of actual sensation has been developing.
In particular, ‘JTC 1/SC 29/WG11’ that is an image related standardization group organized by ISO/IEC has proposed a file format of a stereoscopic video for storing and reproducing stereoscopic video and has discussed a method of effectively optimizing the file format.
The known stereoscopic video file format relates to an image of binocular disparity, which includes a variety of information such as information showing an arrangement form of a left image and a right image, information informing whether or not to include a mono image such as intermediate insertion advertisement, recommendation display information, and camera parameter information, information on whether or not to refer to other images and information indicating what image is referred to.
However, the known stereoscopic video file format generally includes recommendation display information and camera parameter information on each image, such that the data amount is increased because it does not exclude the overlapping portions, which degrade efficiency. In particular, when a video stream called an element stream (ES) has 2ES, in which the left image and the right image are each encoded, almost all or all of the corresponding information of the left image and the right image overlap.
FIG. 1 is a structural diagram showing stereoscopic video stream structure of 2ES according to the related art.
As shown in FIG. 1, the stereoscopic video stream of 2ES is configured to include left ES, right ES, two ESs. Each ES may include a plurality of stereoscopic image frames S1 to Sn and intermediate inserted mono image frames M1 to Mn.
Each stereoscopic video stream is stored in a place called a trak box together with the stereoscopic camera and display information (SCDI) that shows the camera parameter and recommendation display information. At this case, the stereoscopic camera and display information almost all or completely overlaps between the left ES and the right ES. Since it is impossible to refer to the inter-trak box, the structure according to the related art cannot essentially exclude the above-mentioned overlapping.
In addition, when one image within one ES refers to other images, too many images refer to one image or when the reference relation is entangled, the complexity of the file format increases.
In this case, in order to see what image refers to what image during a process of analyzing the file by the computer, the reference information on all the images should be analyzed, such that it is impossible to configure an initial map.